Apple has released the MacBook Air SMC Firmware Update 1.2. According to the company, this SMC firmware update adds compatibility for the latest service replacement batteries. To complete the firmware update process, users should follow the instructions in the updater application in Applications/Utilities/MacBook Air SMC Firmware Update.app. The updater will launch automatically when the installer closes. The MacBook Air SMC Firmware Update 1.2 weighs in at 623KB and requires Mac OS X 10.5.7 or later.